1. Field of the Invention
The present invention generally relates to a thermal insulating body for thermal insulation, wherein the body essentially consists of a shell, or casing, or covering, which can be evacuated and which is filled with a solid, microporous thermal insulator.
2. Background Information
The insulation principle of the Dewar flask is known. This principle is based on the evacuation of a cavity which can be sealed gastight. In vessels such as the Dewar flask, the container walls are generally also heat-reflective, to minimize the conduction of heat by radiation.
Thermal insulation bodies based on pressed, microporous thermal insulating material are disclosed in European Patent No. EP-1064006. It is known to provide such bodies with a full or partial gastight shell, and to set the pressure inside the gastight shell to at least 20 mbar. It is also known to use a compound film made of thermoplastic material, with a metal layer on one side, as the shell material.
German Patent No. DE-2615299 discloses the manufacture of a container for thermal insulation bodies, such as those just described, from thin sheet metal, and discloses connecting the bottom and top areas by very thin, creased, or flanged, metal foils. The same process is also proposed in German Patent No. DE-3630399.
German Patent No. DE-3108810 relates to insulation, having an elasticity of elongation. This insulation includes panels with lateral surfaces oriented in pairs, parallel to one another, and of strips of a thermal insulation material which elastically deforms in only one direction. The strips are attached by adhesive to one another and to the panels at the contact surfaces.
Essentially, all the known thermal insulating bodies have the disadvantage that they tend to be very complex and expensive to manufacture, or tend not to meet all the requirements for compression strength and rigidity.